Calculating the History of LED Calculator Watches

Playboy magazine, June 1975...A gift-giving advertisement with ideas for dads & grads included this guy hidden in the back. The Calcron LED Wrist Calculator. Likely the first public offering of it's kind.

Obscure company Uranus creates a very unusual calculator watch with revolutionary "touch-friendly" buttons. (Most up to this point required a stylus pen for calculations) Sadly, very few exist today and even less in working condition. Both rarity and eccentricity makes this the most valuable calculator watch to collect. Article Link

Hewlett Packard's appropriate contribution to the appendage calculation device. Article mentions "about 50,000 HP-01s had been made, of which about a half had been purchased by a Saudi prince. Half the rest were sold through shops, then the remainder were sold to HP employees at a clearance price." Today, they are one of the most collectible. Article Link

Sinclair's "home assembled" offering (without time function) and ultimate failure due to ill-fitting parts. Article mentions "more than 10,000 Wrist Calculators were sold to masochistic hobbyists from all parts of the world." Article Link

Hughes Aircraft Company (as in Howard Hughes) created this super-block calculator watch between 1976 and 78. One of the most outlandish due to it's massive metal casing. Worn by Lorne Greene and other cast mates on the 70's show Battlestar Gallactica. Article Link